#6. Texas Instruments TI-99/4 (1979)
Texas Instruments' foray into the home computer market didn't last long, and the TI-99/4 offers a few clues as to why. At a time when all other home machines connected to your television, the 99/4 worked only with its own display--which was in fact a bulky 13-inch Zenith TV. Its keyboard came with Chiclet-sized keys more appropriate to one of TI's hand calculators, and like your computer-illiterate mother-in-law, the machine could type only in SCREAMING CAPITAL LETTERS.
Two years later the company released the TI-99/4A, which featured more powerful processors, a better keyboard, the ability to plug in your own monitor, uppercase and lowercase letters, and a price tag less than half the TI-99/4's $1150. But it wasn't enough. TI exited the home PC biz a few years later, focusing exclusively on laptops.